Occurrence of hypertension among patients with opioid use disorder in methadone maintenance treatment

Background: Patients in methadone maintenance treatment (MMT) may develop age-related medical problems, but hypertension (HTN) proportion and its occurrence during MMT have not been studied yet. We aimed to evaluate changes in blood pressure (BP) during MMT and characterize current HTN. Methods: Of all 1098 ever admitted MMT patients, those with ≥2 BP follow-up measures were included (n = 516), of them all current patients (N = 245) tested for HTN (systolic BP ≥140 mmHg or diastolic BP ≥90 were detected twice (one week apart) were considered as affected with HTN. Current and earliest during the first, and latest year in MMT of body mass index (BMI), BP, methadone dose and serum level, and drugs in urine were analyzed. Results: HTN was detected in 89(36.3%) of the current patients. The HTN and non-HTN groups did not differ by sex (P = 0.6), age (P = 0.2), and duration in MMT (P = 0.6), but had higher BMI (27.9 5.2 vs. 25.6 5.2, respectively, P = 0.001) and fewer had positive urine test findings for any substance (31.5% vs. 44.9%, P = 0.04). Comparing their earliest measures (before 11.9 5.8 years), BP and BMI increased more among the hypertensive group, independent of methadone dose and serum levels, which significantly reduced over the years. No drug abuse was associated with increased BMI and BP. Conclusions: Weight gain was associated with BP elevation and characterized patients who succeeded in drug abstinence during MMT. Healthy nutrition education at admission to MMT may reduce the incidence of weight gain and HTN, therefore identifying HTN and offering treatment for this highly prevalent life-threatening condition among middle-age and older patients in MMT is recommended.